Serum pemphigoid antibodies in 76 patients: ocular and other sites compared

Our data was collected to evaluate the sensitivity, specificity, and differences compared to controls, of a panel of tests and their combinations, for serum pemphigoid autoantibodies in 76 mucous membrane pemphigoid (MMP) patients. This was done to compare those with or without a positive direct immunofluorescence (DIF+) result to test our hypothesis that a panel of serum pemphigoid autoantibody tests, and their combinations, might be used to confirm an immunopathological diagnosis of MMP in DIF negative patients with ocular involvement. The hypothesis was tested by evaluating the sensitivity and specificity of tests and their combinations for cases with that of 45 age, sex, race matched controls. The MMP patients had a clinical diagnosis of MMP with or without a positive DIF using defined criteria in a data collection tool. The number of controls was chosen a priori to give an 80% power to detect a difference in the proportions of BP180-NC16a autoantibodies. This was calculated using data from Wieland CN et al. [Wieland CN, Comfere NI, Gibson LE, et al. Anti-bullous pemphigoid 180 and 230 antibodies in a sample of unaffected subjects. Arch Dermatol 2010;146(1):21-5] on age, sex stratified controls having detectable levels of these in 14/337 (4.15%), and our pilot data in our MMP cases in which 8/32 (25%) had detectable levels. Seventy-six MMP patients were prospectively phenotyped using a data collection tool and matched with 45 healthy age sex matched controls. All patients and controls had serum collected and this was tested for the presence of pemphigoid serum autoantibodies using a panel of 5 tests. The sensitivity and specificity of autoantibody detection, Youden’s index, and significant differences, compared to controls, for individual tests and test combinations were evaluated.本研究采集数据的目的是，针对76例黏膜类天疱疮（mucous membrane pemphigoid, MMP）患者的血清类天疱疮自身抗体，评估多项检测及其联合检测的灵敏度、特异度，以及与对照组的组间差异。本研究通过对比直接免疫荧光（direct immunofluorescence, DIF）阳性（DIF+）与阴性的患者数据，验证下述假说：针对血清类天疱疮自身抗体的多项检测及其联合检测，可用于确诊伴眼部受累的直接免疫荧光阴性患者的黏膜类天疱疮免疫病理诊断。本研究通过评估检测方法及其联合检测针对病例组与45例年龄、性别、种族匹配的对照组的灵敏度与特异度，完成该假说的验证。纳入研究的黏膜类天疱疮患者均通过数据采集工具中的预设诊断标准确诊，部分伴随直接免疫荧光阳性结果。对照组的样本量通过事前功效分析确定，以保证有80%的检验效能，检测出BP180-NC16a自身抗体阳性率的组间差异。该功效分析基于Wieland CN等人的研究数据[Wieland CN, Comfere NI, Gibson LE, 等. 健康人群样本中的抗大疱性类天疱疮180与230抗体. 《皮肤病学文献》, 2010;146(1):21-5]：按年龄、性别分层的健康对照中，14/337（4.15%）可检测到上述自身抗体；同时结合本研究的预实验数据：32例黏膜类天疱疮患者中有8例（25%）可检测到自身抗体。本研究通过数据采集工具对76例黏膜类天疱疮患者进行前瞻性表型分型，并匹配45例年龄、性别匹配的健康对照。所有患者与对照均采集血清样本，采用包含5项检测的组合，检测血清中类天疱疮自身抗体的存在情况。本研究评估了单项检测及联合检测的自身抗体检测灵敏度、特异度、尤登指数（Youden's index），以及与对照组相比的组间差异显著性。